Example embodiments relate to an image sensor, and more particularly, to methods of modeling integrated noise in an image sensor and to methods of reducing noise in an image sensor using integrated noise modeling.
Images captured by an image sensor include noise of various types, and the adverse impact of the noise can increase as images sensors are made more highly integrated to reduce the size of portable devices such as digital cameras, camera phones, and so on. As a result, techniques for reducing image sensor noise have become more important with device miniaturization.
In most conventional techniques, the noise caused in the image sensor is assumed as an Additive White Gaussian Noise (AWGN) having a fixed deviation with respect to brightness or intensity of the captured image. A captured image includes noise depending on its intensity, and the conventional techniques adopting the AWGN assumption are limited in removing noise from the captured image. Other conventional techniques based on noise modeling have not been sufficiently developed, such that only a shot noise is considered into the noise modeling. As such, conventional techniques cannot sufficiently reflect various noise types, and thus image quality remains degraded even after the captured image is processed to remove the noise.